The following description is provided to assist the understanding of the reader. None of the information provided or references cited is admitted to be prior art.
Nanoparticulate matter on the order of hundreds of nanometers or less from anthropomorphic and natural origins has increased dramatically with modern manufacturing, pervasive use of consumer electronics, and in medical applications. Traditionally, particulate is removed from a fluid using a physical filtering system. For example, in a heating-ventilation and air conditioning (HVAC) system, particulate can be removed using fiberglass or spunbound filters, charged plates, or ceramic beads that are interposed in the fluid flow. In liquid fluids, various mechanical filters can be used to remove particulate from a liquid. However, a physical filtering system restricts the flow of the fluid resulting in higher energy costs for moving the fluid and frequent maintenance. Additionally, a physical filtering system can become easily plugged.
There is an interest to use acoustic energy, particularly ultrasonic energy, to concentrate particles efficiently in liquid phase fluids. The concepts of ultrasonic energy in fluids can be applied to flow cytometry, microfluidics, and other liquid phase applications. Ultrasonic energy can be used to separate out micron-size biological molecules, such as cells, etc. using liquid filled cavities on the order of millimeters.